Well, I live in Southern California (HB), which is kind of ironic since it usually has everything around and yet, neither Home Depot or Walmart stores around my location sell CRC Heavy Silicone or Jig a Loo. There's some other silicone sprays such as Gunk ___, but I can't clearly recall its name. When you guys mean you got it from Home Depot and other stores similar to it, do you mean recently? I have emailed some of the stores online and they claim that they don't stock them in any local stores.
For example, Home Depot's site even says that they stock Jig a Loo only online. Then again, the online store itself could be outdated, wrong, and the person I was talking to gave me misleading information. It's better to just buy it online, but you have to pay by credit card usually and you also have to wait, two disadvantages that some people don't want to do.